I have to say, it looks like a very nicely done inlay if it is a copy someones done. In fact, I like it so much, I did a digital recreation of it by tracing the scan, as I've done with the proper booklets that came inside the big boxed titles.

The illustrator file does have guides indicating where to fold, but I could add those to a printable PDF if anyone wants it.

The text is all a bit misaligned, so I've 'subtly' corrected it and straightened it in this version. Also moved the 2nd and 3rd pages left a little, as they sit very close to the folds. Perhaps thats an indication that its indeed a reproduction of some kind, as ULTIMATE probably would've been more careful on that unless they didn't care much as it was a cheaper version.

I think it would be best to disregard the full vectorised one, as that was really just an experiment. Clearly the one with the elements used from the poster is better, and allows the images to be compressed within the PDF, giving even the Hi-res one as only 3.5mb-ish.